Question – If i get a green car

If i get a green card how long have i to be in USA.in a year to retain my green card status

Question – Hello , I am a natur

Hello , I am a naturalized USA citizen over 24 years old , I am trying to sponsor my mom who came illegally to the USA back in 2000. I have a little brother who is 14 years old , who was born in the USA. My fear is that, i have been told that by me processing the sponsorship to my mom , that she could be asked to go back to Bolivia , but that i could apply for unlawful presence waiver to prevent the 10 years bar. My question is can my little bother who definitely needs my mom be a reason for my mom to qualify the unlawful presence waiver and be able to come back to USA to be back to being with my underage little brother . I am so afraid to proceed with the sponsorship application and leave my little brother without a mom. I also have another 21 year old brother who is under DACA. Who could also be affected by my mom not being back to the USA. Can my 14 years old little brother qualify as the relative who will be in hardship if my mom is not present in the USA?